Optical binocular instrument



Patented Sept. 4, 1923.

UNITED STATES 1,467,213 PATENT OFFICE.

EMIL WESSELY AND JOHANN SCI-ITER, OF VIENNA` AUSTRIA; SAID SCI-ITERASSIGNOR OF HIS ENTIRE INTEREST TO THE FIRM OESTERI{.UNG. OPTISCHEANSTALT C. P. GOERZ GESELLSCHAFT M. B. H.. 0F VIENNA, AUSTRIA.

OPTICAL BINOCULAR INSTRUMENT.

Application filed November 5. 1921.

[0 UU yw/mmv it may concern.'

Be it known that we7 EMIL VESSELY, docol' medicine, a citizen of theRepublic of Austria. and resident of Vienna, Austria, and JoHANx SoHmR,a citizen of the Bepub'lic of Czechoslovakia, and resident of Vienna,Austria, have invented certain new and useful Improvements in OpticalBinocular Instruments, of which the following is a specification.

Our invention relates to optical binocular instruments for inspectingnarrow cavities more particularly in the human and animal body.

Instruments of this class have heretofore been constructed with twopairs of plane mirrors, one pair for each eye, mirrors of each pairdiverging to such an extent toward the object to be inspected that thediverging rays going from the object to the said pairs of mirrors passedin parallel directions through oculars in front of the eyes of theobserver.

Instruments of this old construction are not only complicated andexpensive and moreover difficult to clean and stcrilize, which is a veryserious drawback when the instrument has to be used for surgicalpurposes, but are also deficient from an optical point of view as thefield of vision is greatly limited and the rays come in paralleldirections into the two eyes of the observer. so that the images appearflat.

rIhe object of our invention is to provide a. binocular opticalinstrument for inspecting narrow cavities which is simple and cheap inconstruction7 which can be readily cleaned and sterilized and in whichthe rays of light coming from the object to be inspected enter the twoeyes of the observer' of an angle of divergency greater than that atwhich they come from the object.

IVith these objects in view our invention consists in so arranging theinstruments of the class above referred to, the two mirrors of each pairthat they converge towards the object to be inspected.

In the annexed drawing Fig. l shows diagrammatically an instrumentembodying our invention. Fig. 2 shows diagrammatically a modificationthereof.

In Fig. 1, S1, S3 and S2, S4L are two pairs of vertical plane mirrors,one for each eye of the observer which are arranged, sym- Serial No.513,068.

metrically to the vertical plane of symmetry of the two eyes of theobserver. The angles a between this plane of symmetry and the outermirrors S1 and S2 are preferably nearly 15 and according to ourinvention the angles between this plane of symmetry and the innermirrors S3 and S4 are smaller than the angles a so that the two mirrorsS1 S3 and S2, S1 respectively of each pair converge towards the side ofthe object G to be inspected which for convenience of illustration isassumed to be in the said plane of symmetry. Rays G b1 and G b2, goingfrom the object G to the inner mirrors S3 and S2, respectively arereflected there in the directions b1 c1 and b2 c2 respectively and inthe points c1 c2 of the outer mirrors S1 S2 respectively, they arereflected in the directions c1 A1 and c2 A2 into the eyes A1 A2respectively of the observer. The lines c1 A1 and c2 A2 intersect eachother in the point B of the said plane ot' symmetry which point formstwo coincident images B1 B2 of the object inspected. The lines b1 c1 andb2 c2 form part of the geometrical auxiliary lines B1 K1 and B2 I@ usedin constructing the reflected rays in the well known manner indicated inFig. 1. As is clearly seen from Fig. l the angle A1 B A2 formed by therays going from the image B to the eyes A1 A2 of the observer is notablygreater than the angle b1 G b2 of the corresponding rays coming from thepoint G and consequently the object to be inspected is seen by theobserver as if it were open before his eyes and not concealed in anarrow cavity. By properly selecting the angles o: and E the coincidentimages B1 and B2 may be brought as close up to the object G as may bedesired and therefore the observer will see the object to be inspectedas if it were open before his bare eyes.

As shown in Fig. l the mirrors S1 S2 S3 SJK consist of metal or silveredglass, in Fig. 2 for each pair of mirrors S1 S3 and S2 S4 a glass prismof suitable trapezoidal transverse section is substituted. The rayscoming from the object G are reflected at two of the opposite sides.y S1S3 and S2 SA1 respectively of the two prisms while the remaining twosides of each prism have to be so cut that the rays coming from theobject G enter the prisms at a1 a2 and leave the prisms at (l1 d2 atright angles to the said remaining, two sides ot' the prisms in order toreduce the effects of dispersion to a minimum. Otherwise theconstruction shown is the same as that shown in Fig. l. As in themodification shown in ["ifr. 2 the rays 'have to pass through aconsiderable thickness of glass. the points lll Bf are slightly shiftedtrom the positions /rfl and /L'l resijcctivel)v which theyY would occupyif metal or silvercd glass mirrors were used. Likewise the points P1 P-`at which the eyes otl the observer would be seen from the point (l areslightly shit'ted from the positions p1 [J2 which the)v would occupy it'metal or silvered glass mirrors were used.

These slight deviations have to be taken into account in determiningrthe exact dimensions of the instrument.

Of course suitable oculars may be interposed between the pairs ofmirrors and the observers eyes if desired. Further the pairs of mirrorsmay be made adjustable to suit the distance between the pupils of the cves ot the observer. Moreover' it desired, the difference of the anglesou and B may be made adjustable to adapt the instrument to eyes ofdifferent observers. As a, rule the instrument will be used vithout anyog more particularly in case of operations in narrow cavities; in thiscase the instrument will be found very advantageous as it is simple,cheap and light and ma)Y be readily cleaned and sterilized. and moreoverpermits to see the object just as clearl \v and truly as with bare eyeswhich greatly facilitates any operation.

The two pairs ot' mirrors or the two prisms may be mounted in an)v knownor preferred manner in a suitable l'rauic and any suitable means beprovided lor throwint;- a pencil of light on the object inspected.

(laim:

In a binocular optical instrument lor inspecting narrow cavities twopairs otI reflecting surfaces symmetrically arranged and inclined to aplane the lilies ot intersection of such plane of symmetry and ot' therefleeting` planes being parallel to cach other, the angles between theouterI reflection surfaces and such plane of s vmmetiv being greater'than the angles between the inner reflecting surfaces and the plane ofsymmetrjv and means for holding the said refleeting surfaces inposition;

In testimony whereof we have signed our names to this specification inthe presence ot' two subscribing witnesses.

DR. EML VESSELY. JOHANN SCI-HER. Vitnesscs ARTHUR BAUMANN, JOHANN BING.

